Multiphase Large Eddy Simulation of a Pulsed Sieve-Plate Extraction Column - 18125

Conference · Sun Jul 01 04:00:00 EDT 2018

OSTI ID:22975320

Theobald, Daniel W.; Hanson, Bruce; Fairweather, Michael; Heggs, Peter ^[1]

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1. School of Chemical and Process Engineering, University of Leeds (United Kingdom)

Presented here is research resulting from a framework of single-phase and multiphase modelling trials. These are intended to accurately simulate the internal flow phenomena arising in pulsed sieve-plate extraction columns representative of those found in industry. Three-dimensional unsteady flow calculations using large eddy simulation coupled with dynamic sub-grid scale modelling have been used to capture the transient effects of sinusoidal flow conditions using the open source CFD code OpenFOAM{sup R}. Multiphase interface interactions are modelled using the volume of fluid method with appropriate heavy and light phase fluidic properties capturing surface tension, density and viscous effects. The system studied consists of a 150 mm diameter column with two perforated plates with a fractional free area of 25 %, operational under 1 Hz pulsing frequency at a 50 mm amplitude and plate spacing of 300 mm. The materials simulated include water (single-phase) and 3 M nitric acid and dodecane / tributyl phosphate mixture at 30 vol% (multiphase). Results are compared with appropriate correlations from literature. The dispersive mixing efficiency of the system was also evaluated via a mixing index value which allows quantification of the ratio of rotational and irrotational flow components. This study has found that the predictive methods employed are effective at capturing the different scales of turbulence present within pulsed sieve-plate extraction columns, and its influence on their operation. As such, the work highlights the ability of large eddy simulation-based modelling to predict the complex flows in such column geometries. Furthermore, the techniques employed provide valuable insight into the hydrodynamic flow characteristics and mixing mechanisms arising within pulsed sieve-plate extraction columns. (authors)

• Research Organization: WM Symposia, Inc., PO Box 27646, 85285-7646 Tempe, AZ (United States)
• OSTI ID: 22975320
• Report Number(s): INIS-US--20-WM-18125
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
97 MATHEMATICS AND COMPUTING
DODECANE
EXTRACTION COLUMNS
HYDRODYNAMICS
LARGE-EDDY SIMULATION
MULTIPHASE FLOW
NITRIC ACID
SURFACE TENSION
THREE-DIMENSIONAL CALCULATIONS
TRANSIENTS
UNSTEADY FLOW